1. Field of the Invention
The present invention relates generally to the control of amplifier common-mode levels.
2. Description of the Related Art
Differential amplifiers are used in a variety of signal conditioning systems (e.g., pipelined signal converters) to generate residue signals for conversion in successive converter stages to thereby provide digital codes that correspond to analog input signals. The accuracy of the residue signals and, hence, that of the signal conversion, is directly related to the performance of differential amplifiers which generally operate in first and second operational modes. It has been found, for example, that poorly controlled common-mode levels can substantially degrade the accuracy of residue signals.